The present disclosure relates generally to dynamic link aggregation in a communications network.
Network devices are interconnected by communication links for transmitting data packets through physical ports. In order to provide redundancy or bandwidth, some networks bundle multiple communication links between a pair of network devices. Link Aggregation Control Protocol (LACP) is part of an IEEE specification (802.3ad) that allows several physical ports to be bundled together to form a single logical channel. The logical channel has multiple links that connect the network infrastructure device and the network device.
One example of such link aggregation implementation is EtherChannel. In conventional EtherChannel, load sharing is statically configured. EtherChannel frame distribution is based on an algorithm that selects a port based on addresses and session information. For example, the frame distribution may be based on a source address, destination address, or both source and destination addresses. In statically configured channels, load balancing is achieved by assigning each port an address so that all the physical ports in the port group are used. Frames with the same addresses and session information are always sent to the same port in the channel to prevent out-of-order packet delivery. Static link aggregation does not take into account the size of frames or amount of traffic assigned to each port, or variation in traffic over time, and therefore results in limited load balancing and utilization of the link bandwidth.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.